


Your Body Changes Everything

by neymovirne



Category: Harry Potter - J. K. Rowling
Genre: Anal Sex, Bisexual Severus Snape, Book 5: Harry Potter and the Order of the Phoenix, Bottom Severus Snape, Genderfluid Character, Metamorphmagi are good with their tongues, Metamorphmagus Sex, Oral Sex, Other, PWP, Rimming
Language: English
Status: Completed
Published: 2020-10-04
Updated: 2020-10-04
Packaged: 2021-03-07 21:02:08
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,240
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26814076
Author URL: https://archiveofourown.org/users/neymovirne/pseuds/neymovirne
Summary: Tonks comes to the Order meeting as a man, and Severus is intrigued.
Relationships: Severus Snape/Nymphadora Tonks
Comments: 16
Kudos: 124





	Your Body Changes Everything

**Author's Note:**

> Thousand thanks to wonderful [Sadsnail](https://archiveofourown.org/users/Sadsnail) for betaing this fic.  
> Title stolen from a song by Perfume Genius.

An unfamiliar red-headed man strides into Grimmauld Place’s living room, his gait full of confidence until he stumbles over the edge of the frayed Persian carpet and almost falls into Severus’s lap.

“Sorry, Professor,” the man says with a cheeky smile.

Severus glares. “Who are you?”

The man’s hair turns purple, and he winks.

“Kindly remove yourself from me,” Severus says crossly, pushing the metamorphmagus away. He never managed to instil any fear in her when he was her teacher, and now she has taken to talk to him with the overfamiliarity she treats everyone else short of the Headmaster.

“Tonks! Little cousin!” Black puts his glass on the table, the amber liquid sloshing over. The meeting hasn’t started yet, and the mutt is already drunk. “Come sit with us! That greaseball would never appreciate a good prank!”

Severus curls his lip in derision.

“No pranks today.” Tonks perches herself of the armrest of his chair, in no hurry to join Black and his pet wolf, who is looking worse for wear the day after the full moon. “I came here right from the stakeout.”

“I’ve always wanted to ask.” Black leers. “When you turn into a man, do you turn… completely?”

“Sirius!” Lupin elbows him, looking scandalised.

Tonks is saved from having to reply by the arrival of the Weasleys. Severus would never be so rude as to ask a question like that, but he glances at her furtively. She has reversed her face to her usual look at Molly’s prompting, and her shoulders lost their broadness under a shapeless jumper, but Severus can bet that he spots an outline of a bulge as she sits on his armrest, inches away from him. He occludes, willing the heat away from his ears. These are not the appropriate thoughts to have about a student, even a former one.

The meeting is a waste of his time. Severus gives a brief report, an abridged version of what he already told Albus. The Dark Lord is focused on obtaining the prophecy, no changes there. Black is doubting his loyalties again, and they exchange a few insults, all par for the course. At one particularly heated moment, a hand graces his shoulder, making him roll back the hex that’s on the tip of his tongue. Severus looks up sourly. Damned girl, spoiling his fun. These squabbles with the mutt are the closest thing that passes for the entertainment these days, since he certainly won’t have any when he returns to the castle with its pink toad and dunderheaded students.

He is usually the first one out of the door, but this time he lingers for some reason. Tonks ends up leaving at the same time as him, narrowly avoiding the troll leg umbrella stand she usually trips over by pressing into his side.

“You were interested in the answer to Sirius’s question as well, weren’t you?” she asks with her usual forwardness.

Severus sputters. “This is none of my business, Miss Tonks.”

She makes a face. “Don’t ‘Miss’ me. I haven’t been your student for more than four years.”

“Shall I call you Nymphadora, then?” Severus asks, knowing full well her dislike for the name.

“Don’t you dare, _Severus_.”

They stand on the porch, and although the autumn night air is chilly, neither is eager to disapparate. Tonks sighs, and suddenly her face is so much closer. Her soft lips taste of lemon tarts Molly brought to the meeting, and her tongue is doing things it has no business doing in his mouth. Her hips press closer, letting him feel the answer to the earlier question.

Severus forces himself to step away—how did his arms end up on her waist?—and opens his mouth to tell the girl off for her presumption. What comes out, however, is, “Here’s not the place for this.”

Something like relief flashes in Tonks’s eyes before she grins. “I’ll apparate us to mine, then.” She sounds slightly breathless, but then, so is he.

“This is madness,” he tells her but doesn’t protest as she takes him by the arm and apparates into her bedroom.

“Sorry for the mess.” She pushes a Weird Sisters T-shirt and some folders from her bed, not sounding particularly apologetic.

Before Severus can so much as to look around, she is kissing him again, nimble fingers undoing the buttons on his robe. He shrugs it off while she slips out of her sweater, revealing a small but definitely feminine braless chest.

“Do you want me to make them—”

“No. Don’t change anything.” Severus pushes her to sit on the bed, and with a joyous laugh, she follows, falling backwards with her arms stretched wide. Her breasts are just the perfect size, he thinks, cupping them and tracing his thumbs around her hardened nipples. He leans over to take one and then the other into his mouth and then kiss down to where the bulge is tenting her low hanging jeans. He undoes the fly, and his mouth waters at the sight. “No pants, Miss Tonks? How naughty.”

“Not today.” She laughs breathlessly, raising her hips so he could pull down her jeans.

He is not particular about his partner’s exact set of genitals, but with cock, he never has to guess if they truly want him. As is probably to be expected given her abilities, Tonks’ cock is a thing of beauty, thick and long and _hard_ , surrounded by a neat patch of purple hair. Severus refrains from commenting on the colour choice in favour of taking the cock into his mouth and giving an experimental suck to the tip. Tonks’s breath hitches, and she visibly fights to keep her rounded hips down.

“Fuck, Severus.” Her eyes, heavy-lidded and dark, watch him in wonder.

Is it a one-time experiment, or does she prefer it that way, Severus longs to ask. Hardness and softness blend so seamlessly in her: the stiffness of her erection and her strong thighs that experienced countless Auror drills, and the delicacy of her breasts, a curve of her waist. He doesn’t say anything, of course, and instead takes her fully into his mouth, caressing her tight balls at the same time. Her hand winds up in his hair, which is usually the one thing he never allows. But Tonks cards her fingers through it, not quite tugging, and he redoubles his efforts, relaxing his throat and taking her even deeper.

“Oh, Merlin.” She shudders, delightfully vocal. “You need to stop, or I’ll come.”

Severus lets her out of his mouth, saliva mixing with bitter pre-come. “Why don’t you, then?”

“There’s something I want to try first. You’re going to like it.” Her pink tongue flicks between slightly parted lips, suddenly long and thin and forked, almost like a snake’s. “And why are you still in full kit?” She pouts at his shirt.

Excitement running through his veins, he hastily undresses, leaving only his undone shirt on. He catches her hand as she tugs at it. “Leave it.”

“I’m not bothered by your mark,” Tonks says, interpreting his reluctance correctly.

“Well, you should be.”

The mood shifts, but she doesn’t allow him to raise his usual barriers. Her arms encircle him from behind, holding him tight for a moment, and she gently peels off the shirt. Severus allows her, letting his hair fall over his face.

“So you fucked up when you were a kid,” she whispers into his ear. “And you’re risking your life to make up for it. You are brave, and you’re good, Severus Snape.”

“Don’t presume you know anything about me.” He steps away. “I’m not any kind of Gryffindor hero. You’d be exceptionally stupid to romanticise me or my motivations.”

“Oh, I know you’re a complete bastard. That’s part of your charm.” She chuckles. “Let me make you feel good.”

He finds himself on his hands and knees, and a cleaning charm rushes over him. There are lips on his lower back, and a tongue, too long and agile to be completely human, dips into his crack, tracing a line to his balls before returning to circle his rim. His erection, that has flagged a bit at the reminder of his past regrets, is back to full hardness in an instant, and he bites his own tongue to suppress a moan. Lick and press, and another lick... Severus should probably feel embarrassed at how quickly he has come undone, canting his hips and spreading his legs wider, but finds that he doesn’t care. No one has ever done this for him before, but he already knows that no one else can ever compare.

“Deeper,” he grunts, shaking with need, and Tonks obliges, reaching farther and farther until she teases the spot inside him that no ordinary tongue could reach.

“You always said I should learn to hold my tongue. Aren’t you glad now that I never did?” She asks between licks, inches from his oversensitive skin, and plunges back, grazing his prostate again. His knees are almost buckling under her ministrations.

“Fifty points to Hufflepuff.” Suddenly, even this is not enough. He waves his hand to summon a jar from his moleskin pouch.

The tongue retreats, allowing him to catch his breath, and Tonks catches the jar mid-flight. “Always prepared, are we? I have my own lying around somewhere here, but I’m sure your stuff is better.”

“Naturally it is.”

“Can I?” Two slick fingers press inside him, moving hesitantly at first, as if her tongue hasn’t been doing wonders of serpentine acrobatics there not a minute ago. Soon, another one joins them, and Severus’s thighs quiver in anticipation.

“Now.”

“Are you—”

“If you ask me if I’m sure, I’ll hex you.”

“Gotcha.”

He feels the press of her cock at his entrance, infuriatingly slow, and thrusts back. The sudden intrusion is almost painful enough to regret his impatience, but the stretch and the promise of fullness are worth it.

“The way your arse is taking my cock… It’s the hottest thing I’ve ever seen,” Tonks moans in between shallow thrusts, her fingers digging into his hips. One of her hands moves to splay across his spine. “Arch your back,” she exhales.

“Bossy witch,” Severus grumbles but obeys, but not before clenching his arse around her.

“Yes, like that. Oh God, that’s...” With a strangled noise, she pulls out almost completely before slamming fully in, her balls slapping against his skin with the dirtiest of sounds. It seems to make them both lose what little control they have, Tonks pounding into him, and Severus pushing back to meet her hips halfway.

She changes the angle and finds his prostate again; that’s enough to render Severus completely incoherent. He knows he won’t last long, even without touching his own cock. When she leans over to suck the skin on his shoulder, surely leaving a mark, it’s the sensation of her tits against his back that makes him explode, rather than her hand finding its way between his legs.

He allows Tonks to chase her own release for a few more thrusts before his knees finally give in. They rock together for a while, but his hole is getting too sensitive, and Tonks, sensing his discomfort, finally pulls out. Her tongue returns to his rim for a moment, and it’s almost too much. The sound he produces is dangerously close to a whimper, but Tonks doesn’t comment on that. Instead, she moves to lie next to him, her breathing is still ragged, and gives him a sated smile.

“This was incredible,” she says.

“Indeed.”

He turns to lie on his side, truly relaxed for the first time since the Dark Lord’s return. Tonks’s cock has disappeared, leaving her fully female.

“I want to ride you, as a girl,” she declares. “You do like pussy as well, don’t you?”

Severus squints to look at her dilated pupils. “Are you on some energy potion?”

She laughs. “Not now!”

“It would be unwise to continue our... association.”

“Don’t worry, I won’t be falling into your lap in the middle of the Order meetings anymore. It’ll be our little secret.”

He narrows his eyes at her. “Did you do it on purpose today?”

She sticks out her tongue at him.

“Very mature,” he says, reluctantly getting up to retrieve his clothes.

“You liked it.” The tongue turns snake-like again and flicks at him.

“Do you have to concentrate all the time on the body parts you are changing?” he asks curiously.

“With the more unusual shapes, yes. But if you’re asking about that dick, having it feels as natural as a vagina. I don’t spend much time as a man, or anything in between, because people just don’t understand—at best, they think it’s a prank, like Sirius today—but it feels just as right.”

“Black and his pranks,” Severus mutters darkly, buttoning up his shirt. “People are morons,” he says louder.

Tonks rises to steal one last kiss from him before he disappears in the fireplace. His body feels deliciously fucked out, and he knows he won’t say no to a repeat performance. For some unfathomable reason, the girl seems to like him, and he... Well, _he_ is appreciative of her fluid nature, and will be recalling it every time he tries to sit tomorrow. He would almost feel pity for his first class in the morning if it wasn’t Gryffindor-Slytherin fifth years.

The green flames hide his satisfied smirk.

**Author's Note:**

> Thank you for reading!


End file.
